20 FOREST ENTOMOLOGY. 



mites or otherwise associated with them. He says they were divided, 

 (where considered as micro-fungi) into three orders viz., Taplirina, 

 Fr., Erineam, Pers., and Phyllereum, Fr. The illustrations as given 

 by Frank are suggestive of this being rather an interesting microscop- 

 ical study, inasmuch as we see the contrast of normal with abnormal 

 hairs through the action of mite agency. In some cases the apparent 

 cluster of hairs may, on examination, prove a genuine micro-fungus, 

 so that, by careful microscopical observation, the student can be 

 acquiring knowledge in a kindred subject. 



With regard to the " blind bud " on black currant, it may be noted, 

 as showing the history of the study, that the first authentic public 

 announcement of the existence of the disease was made at a meeting 

 of the scientific committee of the Eoyal Horticultural Society held on 

 March 2, 1869 : 



" Specimens of a disease in shoots of black currant from the Eev. 

 A. Fitch were then produced, Mr Berkeley remarking that the outer 

 bracts were hypertrophied, and in consequence the delicate divisions 

 of the inner part of the bud were badly nourished, and death ulti- 

 mately ensued. The chairman pointed out its probable analogy with 

 the galls in hazel produced by a Cecidomyia, which was confirmed by 

 Prof. Westwood, who stated that the disease in black-currant shoots 

 was produced by an extremely minute four-legged Acarus."- ' E. H. S. 

 Journal,' JSTew Series, vol. ii., pt. 3, 1870. 1 



With regard to the Eriophyidce generally, it may be stated that Mr 

 Andrew Murray was the first to collate the information concerning 

 these mites in a general way, and he gives a very interesting account 

 of them in his ' Economic Entomology.' 2 



Within the last few years elaborate researches have been made by 

 Dr Alfred Nalepa of Vienna, and to his writings all interested in the 

 subject must refer. About forty-five species, arboreal and others, have 

 been found in Britain. He has established various genera, families, 

 and sub - families ; but unfortunately he has seen fit to change the 

 generic name Phytoptus to Eriopliyes, and this term has been adopted 

 by all writers on economic entomology. 



The difference between a healthy and a diseased bud is very 



1 "The Currant -bud Mite or Currant Gall - Mite," by R. New-stead, in 

 Journal of Royal Horticultural Society, vol. xxv., pt. 3. 1901. 



2 Economic Entomology Aptera : South Kensington Museum Science Hand- 

 books. 



